On April 4, 1949, foreign ministers from 12 countries signed the North Atlantic Treaty, known as NATO. That alliance has since grown to include 30 member countries. After Russia attacked Ukraine, more countries have sought to join NATO as protection. The Finnish and Swedish governments formally applied for membership in May 2022. TRT World sat down with NATO's Assistant Secretary General for Emerging Security Challenges, David van Weel to talk about the Russia-Ukraine conflict, the possibility of a NATO expansion and Türkiye's importance in both scenarios.